Pneumatic tire.



M.. A. BEES.

PNEUMATIC TIRE.

' APPLICATION FILED Nov.24,1913. IIEIIEwED Aue. 29. Ism. 1.144,959.

Eatente 31m@ 29, 1915 XIII/amber:

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MAR-ECA. IDEES, OF ST. LOWS, MSSOURE, ASSGNGR T0 THE MEIQ'CAH TIRE COMPANY GF ST. LOUS, MISSOURI, COREQRTIN.

PNEUMTI TIRE.

Lie-ieee,

Specieation of Letters Patent,

pplcaton icd November 24, 1313, Serial Ho. 832,377. Eenewe August 2&2, 914e Serial 33o. 59,263.

v'this specification.

ij; invention reines eo pneumatic tires, or, more Specificaiiy stated, to the casings of pneumatic tires in which iniatebie tubes ae Useii, and. has for its object the producioxi of e tire of this kind comprising piies oi rubberized fabric inc-erp rateo?, in the tire struc'usre as so render the eta'ueture more durable `and iess iiebie to ponctures or ruptures than simile? structures iiczeooie made.

The present invention is in the inoue of en impigovemene upm, the pneumatic tire casing shown and describe in Lea-ers 3.32,#

iieeh 1l, i933, ne Company. nu

ne tiie shown zuid described in ehe patent menionefi inchxdes e. piuieiij; of plies of fabric joined of rubberized fabric, wih *aile iabic hceot in :di of the plies imifoi-my tensione to, appioXim-eiy, the limit of Jtheir ciastieiy and substantieiiy heid. a?, such degreep tension loy the vuiczmized rubber in 'me 'eine oasng sucure.

Enigmi-ence has Shown that ne casio mafie in ccordarlce with iz-he greet eiumoiiiy and iongeviy, a; A: theae in. the rn ber-ized. ileoiio strecied, es fiescoed. o desfoy ticiy, as comempiated by the potent, EX- pcrie'oce ons hmveveif, Shown with the fabric t. feeeis in, ai?. oi'fiie piies under severe tension, o1' drea'n. vejf tout, as contemplated oy the pnten, they are 'endee moie susceptibio to being; out of reiified.

By my improvement, pi'ociuce o pneumatic tire Stiecture which is much ieee vuinerabie, when he tire is subjected todae ec- 'ion of Sharp objects which tem to cui? or remi @he abie in the tire. This object attain in my Sire by empioying wbh a pig; or plies of fabric, stretched in eecoence Wiii che etif'e heretofore in voffle, piy

y vulcanized mi )et t* diestxretched ply or piies, so that vfii give or yieicl reeiy in' compei'ison to the other ply or plies in which tile threacis, beng iwf-- molly ensioneei, me easily cut ci.' broken. The exensi'olc ply referred to is locatari innermost or neaifest the cavity in the tire, so that it is nearee the iniatzibie inner tube and ii; is, thereore, so positioned as to ce farthest from the Mead of ehe tire against which e object encounteieii upo e roadway Wouici be iii-st diected; 'and mi B being in proximity the inner uoe it ini v tifiiiy receivee the force of said. imiez whe, 4 ansi 'is capabie ci" yieiiling miffei' such force iiseed of being iup'ured, as a nomaiiy teuf Fig. El is e tiene the finished iLife.

my pneumeic tire, Xfire?, form the tir-e sti'oc-ofecpoo e euiobie eniooseiy it 'be positioned' thereon, "o

eventim,

onrei. one miaixiie be eo w" me Shane of igi'ie meoiei. .if Q he heini of robbei'ized' fabric ammg ie miler pig A. may De laid onto the gommer menrei without being ma tensioied ai, siii and in this evene., the zibic threads me preai-iy compecteffi o'bz'ought closer i-cgehez et the Sidesro the immdi'ei by the 115e of 1 og ooe, or other suitzibie smoothing des'- The succeeding jyies of il@ fabric are formed by stretching fabric hands around the periphery of the mandrel, the transverse middle portions of the bands being severely tensioned and pulledA tightly onto the middle portion of the preceding ply. The lmargins of such .bands ybecome wrinkled While their middle portions arebeing Lstretched and distorted to conform tov the shape of the periphery of the mandrel, and the wrinkled portions of the fabric bands are afterward smoothed by the application of milling tools, or in any other suitable manner. After the fabric plies arer formed on the mandrel, beads 1 may be formed at the .edges ofthe fabric, and a layer of rawrubber is applied to the Iouter-- most'fabric ply. The raw tire may then be vulcanized in any suitable manner, but it is vply A-t lsevere tensile strains.

preferably laced in 'avulcanizing mold,v

consistin o mold'sections Q'tted together toprovi e a tire receiving 'cavityv 3. l

4 designates an abutment ring forming a fluid tight joint at the separable edges of 'the- .tile, and 5. is a pipe-.for conducting fluid underpressure to the interior of the'; tire.

The raw tire is preferably separated from the walls of the cavity 3 inthe mold, sorthat the tire .may be expanded by'internal fluid pressure to stretch the fabric structure, placing thethreads of the outer fabric plies B under uniform tension, and preferably stretching-the threads of said plies to, ap-

roximately, the limit of their elasticity.

tris to beundestood that the entire fabric structure is' expanded by the internal Huid pressure, but the threads of the slac inner fabric pl A are not tensioned li e the threads o the outer fabric plies.

As before stated, the inner 'fabric ply is carefully laid onto the mandrel in a manner to avoid unnecessary stretchin of its threads, While the vouter fabric plies are severely tensioned' during the process of building up the fabric structure. Therefore, the final stretching operation, which takes place in the vulcanizing mold, places the outer fabric plies B under a high degree of tension, 'but does not subject the .inner fabric strength of the inner ply is not materially affected by the final stretching operation.

My improved tire possesses all of thev advantages-found in the tire shown in the prior -patent to which I have referred. The

outer fabric plies will resist the service pressure of an inner tube Without ielding in the rubber, and the tire is there ore free fromI internal strains toV which tires are usually subjected by the stretching of the fabric in the rubber. The tensioned fabric pliesr resist the inner tube pressure so that the rubber is not materially stretched by the internal pressure of the tube, and this is quite iin-l portant, for the reason that the unstretched rubber will withstand the service conditions The tensile'4 without rupture for a much longer period of time than tensioned rubber. It is, true that "the 'threads of the stretched outer plies of fabric B areldrawn very taut in the processvof manufacture by the internal pressure v in the'raw or unvulcanized tifs structure, so that such threads do not retain all of their original strengths Obviously, the tensioned. threads may be rended by a vcutting action that would not re`nd untensioned threads. y One of the decided`\ advantages of the sub-l; i

stantially untension inner ply A will now be apparent. This eo paratively'loose orextensible inner ply pl 'sses substantially all of its original strengthl, and ,under ordinary 88,

conditions, it is not'tensipned by the pressure of the inner tube. The tube presses against the inner ply A, but the latter is prevented from stretching by the lign-yielding outery strength until the outer pli are worn away, punctured, or otherwise rup red, and the strong inner ply then comes to service'to resist the pressure of the inne tube, and it always serves to resist the cutting action of an object tending to puncture thertire much A more e'ectually than-it would if the threads were under the same tension as those in the outer plies.

' plies B. The inner ply therefore retains its 35 The invention so far described lies in the highly tensioned fabric plies B adapted to fabric elements. The n fluid under pressure introduced into the raw found in practice that the comparatively un 110 tensioned fabric ply A forms a seal capable of resisting the iluid under pressure, so that the fabric structure is notl in any way injured by the steamer other fluid utilizedin expanding the raw structure.v

l. A neumatic tire comprising a pluv I' rality o outer plies of rubberizedthreads normally uniformly tensioned, and an inner ply of rubberized threads normally `tensioned to a less degree than the threads in Y i said outer plies, the rubber being vulcanized and connecting the various plies into a 'univ tary structure.

2,'A "neumatic tire comprising a plu- 1125 rality o outer plies of rubberized threads' normally-uniformly tensioned to -a degree preventing the extension of the threads by tirevinflatlon pressure, and an inner ply of the highly'tenv10d I,

rubberized threads normally tensioned to a v l i less de e than thethreads in said outer plies, t e rubber being vulcanized and connecting the various plies into a unitary normally uuiforml tensioned to, s. proximately, the limit o elasticity of the t ends, and an inner ply of rubberized threads norte mally tensioned to a less degree than the l0 threads in said outer plies, the rubber being vulcanized and connecting the various plies into a unitary structure.

MARK A. BEES.

In the lesence of.-

E. LINN, E. K. CLARK. 

